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Thomas Kershaw

CIK 1686179 · Chief Technology Officer · last filed 2021-05-19

Thomas Kershaw is a Chief Technology Officer who has filed 27 SEC Form 4 insider transactions across 2 companies since 2016. The most recent filing shows the insider sold $1.1M of MGNI on May 19, 2021. Across all open-market trades the lifetime net is −$11.0M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $11.3M across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$11.26M

Companies

2

Total Filings

27

Lifetime Open-Market Net

-$11.04M

Filer Profile

Reported Address
C/O THE RUBICON PROJECT, INC.
12181 BLUFF CREEK DRIVE, 4TH FL
LOS ANGELES, CA 90094
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
MGNI Chief Technology Officer 473,763 $23.77 $11.26M -$9.52M 7 2021-05-19
RUBI Chief Technology Officer 11 $1.51 $17 -$1.52M 20 2020-06-05

Recent Filings

27 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2021-05-19 MGNI Sell (S) −41,213 -$1.07M EDGAR
2021-04-07 MGNI Sell (S) −100,000 -$4.05M EDGAR
2021-04-05 MGNI Grant (A) +31,760 $0 EDGAR
2021-02-18 MGNI Mixed — -$2.71M EDGAR
2021-02-18 MGNI Mixed −30,393 -$495.6K EDGAR
2020-11-18 MGNI Sell (S) −30,393 -$336.1K EDGAR
2020-08-19 MGNI Mixed — -$165.3K EDGAR
2020-06-05 RUBI Mixed — -$73.4K EDGAR
2020-06-05 RUBI Sell (S) −52,285 -$274.6K EDGAR
2020-05-20 RUBI Sell (S) −49,915 -$262.4K EDGAR
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Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.